$_transition-duration: 0.25s;
$_transition-timing-function: cubic-bezier(.645,.045,.355,1);

@function transitionEffect($property) {
  @return $property $_transition-duration $_transition-timing-function;
}

$_all-transition: transitionEffect(all);
$_color-transition: transitionEffect(color);
$_background-transition: transitionEffect(background);
$_border-color-transition: transitionEffect(border-color);
$_box-shadow-transition: transitionEffect(box-shadow);